(1) Field of the Invention
This invention relates to in situ tire inflation inspection and in situ inspection of the tire mate.
(2) Description of the Prior Art
A common problem with dual truck tires is mismate or wrong tire pressure. Because of wear or recapping or mating biased and radial ply tires or other reasons, it is possible for two tires to have the same pressure in a dual pair, but still be mismated. In the event of mismating, one of the tires will carry most of the weight. Because of this excess weight, it will tend to over heat and wear excessively.
Because of the dual relationship of the tires, if one tire is properly inflated, it is difficult to determine whether the other tire is also properly inflated. Inasmuch as many truck-trailer combinations have 18 tires on the ground, it is time consuming to check the pressure of all the tires using a conventional hand gauge. Commonly to get some estimate and to make certain that there is not a deflated tire, often a check will be made by hitting each of the tires with a hammer and from the resiliency of the tire reflected by the bounce of the hammer, a determination is made if the tire is uninflated. However, excessive wear will result if either or both tires is substantially over or under inflated.
The problem of testing the inflation of each tire of a dual pair has been recognized.
Previous workers in the field have suggested that probes could be mounted into a roadway to push against the peripheral face, i.e., the tread of the tire. The amount of deflection or the different pressure between the center of the tread and the edge of the tread was taken as an indication of the inflation. JEHLE, U.S. Pat. Nos. 3,715,720; KRATT, 2,313,156.
Others have used a plurality of spring biased slats and the deflection (or weight) was taken as an indication of tire inflation. MORRIS, U.S. Pat. No. 1,849,730.
Other workers in the field, seeking to test the sidewall for defects, have used rollers along the sidewall of the tire. However, as it is understood, these persons who use rollers on the sidewall were not seeking to determine the inflation of the tire, but were seeking to detect sidewall defects. PUMMILL, U.S. Pat. Nos. 2,251,803; VEALS, 3,303,571.